Poultry Litter as a Nutrient Source for Low Input Forage Systems.

Appropriate management of animal manures is of particular concern in the Shenandoah Valley of Virginia.  Nutrient loading associated with intensive poultry and dairy production is implicated in water quality impairment in the Chesapeake Bay.  Despite the high volumes of manure production, there are still areas of forage production in the Shenandoah Valley that are nutrient deficient, because manures have traditionally been applied to higher value row crops. This study was conducted to compare the effects of poultry litter and inorganic fertilizers on soil fertility and forage yield and quality. Two sites were chosen in the Shenandoah Valley, one in Rockbridge County and the other in Northern Shenandoah County.  Fertility treatments were: (1) Split application of litter: 67 kg PAN/ha, 26 kg P/ha, applied in the spring and late summer, (2) Inorganic fertilizer at same N and P rates as 1, (3) Single application of litter: 134 kg PAN/ha, 52 kg P/ha, (4) Inorganic fertilizer at same N and P rates as 3, (5) no fertilizer control. Experimental design was a randomized complete block with four replications, and all fertilized treatments received the same annual rate of plant available N (PAN) and P.  The same treatments will be applied to the two sites for two consecutive years, and the data presented will be for the first year’s results. Soils in all plots were analyzed for soil pH, water soluble P, Mehlich 1 P, and organic matter content. Forage measures included yield, crude protein, total P, botanical composition, and fescue alkaloid concentrations.  We will report on early results that indicate improvements in the fertilized plots in soil fertility, forage yields and botanical composition, with some distinct differences between poultry litter and inorganic fertilizer sources. The results of this study should encourage the use of locally available poultry litter to improve forage production.